Scaffold



S. N. DEINES SCAFFOLD 5 Sheets-Sheet 1 Filed June 23, 1966 INVENT ORSTANLEY N. names Oct. 8, 1968 Filed June 25, 1966 5. N. DEINES SCAFFOLD5 Sheets-Sheet 2 INVENTOR STANLEY u. DEINES Oct. 8, 1968 s. N. DEINES3,404,752

SCAFFOLD Filed June 23, 1966 5 Sheets-Sheet 5 a INVENTOR STANLEY N.DEINES BY M Oct. 8, 1968 s. N. DEINES 3,404,752

SCAFFOLD Filed June 23, 1966 5 Sheets-Sheet 4 INVENTOR. STANLEY N.DEINES Oct. 8, 1968 s. N. DEINES 3,404,752

SCAFFOLD Filed June 25, 1966 5 Sheets-Sheet 5 laa 2|6 h i V214 INVENTOR.STANLEY N. DEINES United States PatentO 3,404,752 SCAFFOLD Stanley N.Deines, Denver, Colo. (RR. 1, Oberlin, Kans. 67749) Continuation-impartof application Ser. No. 429,733, Feb. 2, 1965. This application June 23,1966, Ser.

A Claims. (cl. 182-148) ABSTRACT OF THE DISCLOSURE This application is acontinuation-in-part of my copending patent application, Ser. No.429,733, filed Feb. 2, 1965 and now abandoned.

This invention relates to a scaffold and more particularly to avertically extendable scaffold structure having means for supporting adeck in various attitudes and particularly in a disposition inclined tothe horizontal.

In the construction industry, scaffolds are used extensively forsupporting men and equipment in working position adjacent to a buildingbeing constructed.

Scaffolds are used for many other purposes, however, most scaffolds areassembled and disassembled at a job site and such assembly anddisassembly requires con-; siderable time of workmen and imposes someinconvenience in the transportation and use of conventional scaffolds.Further, most scaffold structures are inconvenient for use in supportinga deck in parallel relation to an inclined surface, such as an inclinedceiling or other similar structure adjacent to which workmen areperforming various installations or finishing operations. It has been aproblem properly to support men on a scaffold deck in parallel relationto an inclined ceiling or the like, so that they may work with ease andprecision during the performance of various installations and/orfinishing work, such as plastering or the like. Additionally, prior artscaffolds have lacked economi cally operable power equipment forvertically extending the scaffold and retracting them quickly and tothereby permit simple transportation and set-up of scaffold structuresadjacent to a job site.

Accordingly, it is an object of the present invention to provide a novelscaffold having a generally rectangular structure provided withvertically extendable column structures at the corners of the scaffoldstructure and I 3,404,752 Patented Oct. 8, 1968 2 arrangement ofvertically extendable telescopic column members for a scaffold structurewhich permit the construction of a very compact scaffold which may bereadily and quickly extendable to substantial elevations and which mayalso selectively dispose a deck supported by the column members on adesired inclined position relative to the horizontal.

Another object of the present invention is to provide a novelarrangement of vertically extendable telescopic column members in whicheach assembly of column members at each corner of the scaffold structureof the invention is provided with a pair of hollow cylindrical members,one of which employs an upwardly extending telescopic element and theother supports a downwardly extending telescopic element and wherein apair of hydraulic cylinders at each end of the scaffold are providedwith corresponding downwardly extending and upwardly extending plungers,whereby the hydraulic cylinders cooperate with the column assemblies atthe corners of the scaffold to permit cross bracing readily to beemployed in interconnecting relation with the column assemblies of thecorners of the scaffold. v

Further objects and advantages of the present invention may be apparentfrom the following specification, appended claims and accompanyingdrawings, i'n which:

"FIG. 1 'is an end elevational view of a scaffold in accordance with thepresent invention;

FIG. 2 is a diagrammatic view of the hydraulic power actuating system ofthe invention; I

FIG. 3 is a side elevational view of the scaffold structure of theinvention;

FIG. 4 is a side elevational view of the scaffold structure of theinvention similar to that shown in FIG. 3, but showing the scaffoldstructure vertically extended;

FIG. 5 is an enlarged fragmentary sectional view taken from the line 55of FIG. 1;

FIG. 6 is an enlarged fragmentary plan sectional view taken from theline 6-6 of FIG. 1;

FIG. 7 is an enlarged fragmentary plan sectional view taken from theline 7-7 of FIG. 1; v 4

FIG. 8 is an .enlarged fragmentary sectional view taken from the line88.of FIG. 1, showing by broken lines varying inclined positions of adeck structure of the present invention;

FIG. 9. is a reduced planview of the scaffold of the invention; 1

FIG. 10 is a side elevational view of a modified form of the invention,showing by broken lines an inclined disposition of the platform of theinvention similar tothat shown in FIG. 4;

FIG. 11 is a view taken from the line .11-.11 of FIG. 10, showing an endof the-modified scaffold structure of the invention; :1

-FIG. 1-2 is a fragmentary plan view taken from the line 1212 of FIG.10; and

FIG. 13 is an enlarged fragmentary plan sectional view taken fromtheline 13.13ofFIG. 10..

' Another object of the invention is to provide a novel scaffoldstructure having telescopic vertically extendable column members whichare extendably operable by hydraulic cylinders furnished power by acontained hydraulic system'carried by the scaffold structure.

...A s shown in FIGS. 1, 3, 4 and 9 :of the drawings, the scaffold ofthe invention is a generally. rectangular scaffold having first-andsecond ends 10.and.12 and having opposite sides Hand 16. At corners .ofthese scaffolds are vertically extendable telescopic columnassemblieslS, .20, 22 and 2,4. These column assemblies are arranged'inpairs, the column assemblies 18- and 20 being one pair and ;-the columnassemblies. 221and 24 being another. pair,-.the pairs being'atrespective opposite ends or-first=-and second Another object of theinvention is to provide a power nds n tt e scaffold, 1 1 )-bcSt illFIG;

9.,ofthe drawings. The first pair 18 and 2.0 and the second pair .22 and24 are connected together by removable braces, as will be hereinafterdescribedin detail, so that the pairsof vertically extendable telescopiccolumn members may be maintained in assembled relation as unitaryoperating mechanisms and 'in this manner the braces removably connectingthe pairs of column assemblies together permits the entire scaffoldstructure to be disassembled, if desired, for transportation in compact'form.

Each of the column assemblies18, 20,22 and 24 is composed of threeconcentric telescopic members and the construction of all of the columnassemblies 18,20, 22 and 24 is substantially identical. A

As shown in FIGS. 5 and 7, the column assembly 18 is provided with anoutside hollow cylindrical tubular member 26 internally of which asecond hollow tubular member 28 is disposed and vertically slidablymovable in the hollow tubular member 26. g

The hollow tubular member 28 is provided with an internal bore in whicha third hollow tubular member 30 is vertically slidably mounted, all asshown best'in FIGS 5 and 7 of the drawings. j

The hollow tubular member 26 is provided with a vertically disposed slot32 in the side wall thereof which is traversed by a tubular cross member34 secured by welding or otherwise to the outer" surface of the hollowtubular member 28 at 36 so that when the hollow tubular member 28 movesvertically in the tubular member 26, the cross member 34 may also movevertically in the slot 32.

The column assembly 20 is similar to the column assembly 18, such thatit is provided with a slot similar to the slot 32 in such slot and moveup and down with the respective hollow tubular member 28 of theassemblies 18 and 20.

Interconnecting upper ends of the hollow tubular members 28 of theassemblies 18 and 20 is a secondcro'ss member 38 which may, at itsopposite ends, be welded to the hollow tubular members 28 of theassemblies 18 and 20, respectively.

A third cross member 40 is welded at its opposite "ends to upstandingportions of the hollow tubular members 30 of the assemblies 18 and 20 atlocations above the uppermost end portions of the hollow tubular members28.

The structural interconnection'of the pair of column assemblies 22 and24 is similar to that disclosed in connection with the pair of columnassemblies 18 and'=20, such that there are respective cross members 34,38 and 40 interconnecting both pairs of column assemblies. Thus, a crossmember 40 interconnecting upper ends of the tubular members 30 of eachpair of column assemblies are disposed at opposite ends 10 and 12 of thescaffold, as shown in FIG. 9. Thus, the cross member 40 at opposite ends10 and 12 support planks 42 thereon. These planks 42' are securedtogether at their lower sides by stops 44 or each plank 42 may have apair of individual stops disposed adjacent the cross members 40, suchthat the planks may not slide longitudinally an appreciable distancebetween the cross members 40. In this manner, these stops 44 retain theplanks 42 when they are'moved into broken line inclined positions,disclosed in FIG. 8 of the drawings.

'The hollow tubular members-26 of the column assem blies 20 and 24 areinterconnected by diagonal braces 44 and 46. These braces may be weldedto the hollow tubular members 26 or they may be removably bolted theretoor removably connected thereto in any suitable manner, as desired.Removable connections of the braces 44 and 46 with the hollow tubularmembers 26 will permit the scaffold structure of the invention to bedisassembled so thatthe pairs of column assemblies 18 and 20 with theirinter-'- connecting cross members 34, 38 and 40 may be removably securedto the pair of columnassemblies 22 and 24* together with their crossmembers 34, 38 and 40.

Diagonal braces 48 and 50 interconnect the-tubular members 28 of thecolumn assemblies 20 and 24 and also the assemblies 18 and 22at-opposite sides of the scaffold. Lower end portins'52 and 54 of thebraces '48-and 50,- respectively, are connected'to the cross bars 34while upper members 38, as shown best in FIGS. 4 and of the drawings.The connection of each'upper end 56 and 60 of the braces 48 and 50,respectively, is preferably at the upper end of each tubular member 28above the upper end of the respective tube 26. These brace members 48and 50 may. be-welded in their connections with the cross members 34 andthe upper portions of the tubularmembers 28 or they may be 'bolted orotherwise removably connected to provide for disassembly of thescaffoldinto separate brace components and pairs of column assemblies at theends and 12 of the scaffold to thereby permit complete collapsing of thescaffold to render it readily portable. It will be seen that the planks42 may readily be removed from the cross member '40'to accommodatedisassembly of the scaffold structure, if desired.

Pressure fluid operated hydraulic cylinders 62, 64, 66

and 68 are disposed to elevate the scaffold structure of the invention,the hydraulic cylinder 62 .being provided with a plunger 63 secured at70 by a bracket welded to a cross bar 72 having its opposite ends weldedor otherwise fixed to the tubularmember 26 of the column assemblies 18and 20. A normally upper end of the hydraulic cylinder 62 is mounted ona pin 74 carried by a bracket 76 secured by welding or otherwise to therespective cross member 38, as shown best in FIG. 5 of the drawings.

The hydraulic cylinder 64 is provided with a plunger 78 mounted by a pin80 to a bracket 82 fixed to the cross bar 34. The cylinder 64 is mountedby means of a pin 84 to a bracket 86 and this bracket 86 is welded orotherwise secured to the respective cross bar 40.

' Extension of the plunger 63 from the cylinder 62 causes the telescopicelevation of the tube 28 relative to the respective tube 26 andenergization of the cylinder 64 to extend its plunger 78 causes thecylinder to raise the tubular telescopic element 30 relative to thetubular telescopic element 28 of each column assembly. It will be seenthat the hydraulic cylinder 66 is structurally arranged in an equivalentmanner to that of the hydraulic cylinder of the hydraulic cylinders 64and 66 may permit the scatfold planks 42 to be disposed on an incline,as indicated by broken lines in FIGS. 4 and 8 of the drawings, simply byindependently energizing one of the cylinders 64 and E 66 to a greaterdegree than the other from an elevational standpoint.

As shown in FIG. 1 of the drawings, the hydraulic cylinders 62 and 64are disposed at a location substantially intermediate the columnassemblies 18 and 20 and, likewise, the cylinders 66 and 68 are in asimilar location between the pair of column assemblies 22 and 24.

The cylinder 62, as hereinbefore described, is supported by means of abracket carried by the cross bar 72 and this cross bar 72 is braced nearits intermediate portion adjacent the bracket 70 by means of diagonalbraces and 82 having their upper end portions welded at 84 to therespective outer tubular member 26 of the respective column assembly,all as shown best in FIGS. 1 and 5 of the drawings.

Interconnecting the respective tubular member 26 of the columnassemblies 18 and 20 and also the column assemblies 22 and 24,respectively, is a cross member 86 which is welded or otherwise securedto the tubular member 26 adjacent the connections 84 of the diagonal 20.Thus, vertical loading and stress applied by operation ends 56 and "60of the braces 48'and 50 are connected to] upper end portions of thehollow tubular members 28near 7 diagonally disposed relative to theconnection of the of the hydraulic cylinder 62 is carried by the braces80 and 82 together with the cross member 72 and the cross member 86, ashereinbefore described.

As shown in FIG. 1, it will be seen that the bracket members 86, ashereinbefore described, are substantially upper end of the cylinder 64therewith at 65, as shown in FIG. 5 of the drawings.

As shown in FIGS. 1, 3, 4 and 5 of the drawings, each of the columnassemblies 18, 20, 22 and 24 may be supported on a suitable caster 88 tofacilitate movement of the scaffold of, the invention.

Carried on plates 90 and 100 secured to upper ends of the tubularmembers 80 of the column assemblies 20 and 24 are valves 102 and 104.These valves 102 and 104 are provided with control arms for actuatingvalve elements to control operation of the respective cylinders 62, 64,66 and 68. The valve 102 is provided with two operating handles 106 and108, while the valve 104 is provided with a pair of operating handles110 and 112, as will be hereinafter described in detail, in connectionwith the diagrammatic view of the hydraulic system, shown in FIG. 2.

A motor driven pump 114 is mounted in connection with the cross member72, hereinbefore described, and this motorized pump is adapted to supplypressure fluid through the valves 102 and 104 to the hydraulic cylinders62, 64, 66 and 68, all as shown best in FIG. 2 0f the drawings. Thesecylinders 62, 64, 66 and 68 are double acting cylinders controlled 'bythe operating handles 106, 107, 110 and 112, respectively, of the valves102 and 104, hereinbefore described. An outlet conduit 116 from the pump114 delivers fluid through a spring loaded bypass valve 118 which isadapted to bypass fluid into a reservoir 120, when fluid is not permitedto flow into one of the cylinders 62, 64, 66 or 68. An inlet conduit 122communicates with the inlet of the pump and extends downwardly into alower portion of the reservoir 120.

A hydraulic return line 124 is coupled to individual return lines 126,128, 130 and 132 communicating with the cylinders 62, 64, 66 and 68,respectively.

It will be understood that the valve operating handles 106 and 112 maybe suitably coupled so that both the cylinders 62 and 68 may beenergized at the same time while the operating handles 108 and 110 mayalso be coupled for concurrent operation so that the cylinders 64 and 66may be operated concurrently. Additionally, it will be seen that each ofthe handles 108 and 110 may be operated individually to obtainindividual height adjustment, as indicated in FIG. 8 of the drawings andhereinbefore described, in order to place the platform planks 42 on anincline relative to the horizontal.

The coupling of the valves, as hereinbefore described, may be doneelectrically and these valves may be solenoid valves so that selectiveoperation of these valves may be attained and also it will be understoodthat concurrent operation of these valves may be attained, if desired,particularly the valves controlling the cylinders 62 and 68 should beoperated together while, in most instances, the valves controlling thecylinders 64 and 66 should be operated concurrently. The cylinders 64and 66 should only be energized independently, when it is desired toobtain an incline of the plank deck 42 relative to the horizontal afterthe platform has been substantially elevated to its desired disposition.

As. shown in FIGS. 10, 11 and 12 of the drawings, the modified structureof the invention is provided with four column assemblies 140, 142, 144and 146 located similarly to the column assemblies 18, 20, 22 and 24,hereinbefore described.

Each column assembly 140, 142, 144 and 146 is similar and these columnassemblies are in pairs at opposite ends of the scaffold, as forexample, the column assemblies 140 and 142 form one pair, while thecolumn assemblies 144 and 146 form another pair, all as shown best inFIGS. 10, 11 and 12.

Inasmuch as all of the corner assemblies are substantially identical instructure, the corner assemblies 142 and 146 will be describedgenerally, as shown in the drawings.

As shown in FIGS. 1 and 2, the corner assembly 142 is provided with apair of substantially vertical external hollow cylindrical columnmembers 148 and 149. Telescopically supported in these hollowcylindrical members '148 and 149 are internal column members 150 and152, respectively. The internal column member 150 being extendableupwardly and retractable downwardly relative to the interior of thehollow cylindrical column member 148, while the column member 152 isextendable downwardly and retractable upwardly within the hollowcylindrical column member 149.

Mounted on a lower end of the internal column member 152 is a caster 154and extendably mounted telescopically in an upper end 156 of theinternal column member 150 is an uppermost column member 158.

Secured to an upper end portion of the uppermost column member 158 is across member 160, the opposite end of which is carried by a similaruppermost column member 162 telescopically extendable upwardly from aninternal column member 164 which is telescopically mounted in a hollowcylindrical column member 166 of the column assembly 140. The samecombination of mechanism exists with respect to said pair of columnassemblies 144 and 146.

Planks 168 form a platform extending across the cross members and aplunger 170 of a hydraulic cylinder 172 is connected to an intermediateportion 174 of the cross member 160 by a clevis 176 reinforced by braces178 and 180. The body or cylinder portion of the hydraulic cylinder 172at its upper end is connected to a cross member 182 having its oppositeends supported on the internal column members 150 and 164. This is thegeneral construction of each pair of column assemblies and therespective scaffold structural elements. The cylinder 172 being operableindependently of a cylinder 184 disposed in a similar manner between thecolumn assemblies 144 and 146 at their uppermost column members whichcorrespond with the column members 162 and 158.

A pair of hydraulic cylinders 186 and 188 are secured together andsupported by cross members 190 and 192 at respective upper and lowerends of the hollow cylindrical members 166 and 149 of the columnassemblies 140 and 142. Thus, the cylinders 186 and 118 are fixed to thecolumn assemblies 140 and 142. The cylinder 188 has an upwardlyextendable and downwardly retractable plunger 191 having a clevisconnection 193 secured to the cross bar 182 at normally upper ends ofthe internal column members 150 and 164. The hydraulic cylinder 186 hasa downwardly extendable and upwardly retractable plunger 194 pivotallyconnected to a clevis 196 carried by a cross member 198 having itsopposite ends secured to the downwardly extending internal column member152 and a similar downwardly extending internal column member 200 whichis extendable downwardly from the column assembly 140 in a similarmanner to the telescopically extendable relationship of the internalcolumn member 152.

A hydraulic pressure fluid supply system 202 is carried on a crossmember 198 and adapted to clear the hollow cylindrical column members148 and 149, when the internal column member 152 is in retractedposition relative to the hollow cylindrical member 149. This hydraulicsystem 202 is similar to that shown in FIG. 2 and is adapted, whenenergized, to provide pressure fluid to the hydraulic cylinders 172, 186and 188, as desired, either collectively or selectively such as toextend the scaffold structure of the invention vertically and to permitindependent energization of the cylinders 172 and 184, such that theplanks 168 may be disposed, as indicated by broken lines 169, to placethe scaffold platform on an incline, as desired.

It will be seen that the hollow cylindrical column memher 148 of thecolumn assembly 142 is disposed inwardly with respect to the hollowcylindrical column member 149 from a respective end of the scaffold ofthe invention. Likewise, all the other column assemblies 140, 144 and146 are similar.

A cross brace 204, as shown in FIG. 10 of the drawings, is pivotallyconnected at 206 to a lower portion of the internal column member 152and an opposite end of the brace 204 is pivotally connected at 206 witha member which traverses a slot in the cylindrical member 252, as willbe hereinafter described. This cylindrical member corresponding to thehollow cylindrical member 149 of the column assembly 142. Likewise,another similar cross brace 208 is. pivoted at its lower end 210 toanother of the internal column members 212 extendable downwardly fromthe column assembly 146. The opposite end of the brace 208 is pivotallyconnected at 214 to a member which traverses a slot in the hollowcylindrical column member 149, as will be hereinafter described.Inwardly relative to the braces 204 and 208 are braces 216 and 218,these braces being shown in plan section in FIG. 13.

It will be seen that the braces 216 and 218 at their lower endspivotally interconnect innermost hollow cylindrical members at thecorner assemblies, said innermost cylinders being comparable to thehollow cylindrical column member 148. The lower ends of the braces 216and 218 pivotally interconnect lower ends of these hollow cylindricalcolumn members, while upper ends of the braces, in a cross positioninterconnect upper ends of the hollow cylindrical column members similarto the inner ones 142 or a comparable inner cylindrical member 220,shown in FIG. 3, which forms an element of the column assembly 146.

Additional cross braces 222 and 224 at their lower ends are connected tomembers which traverse slots in the innermost hollow cylindrical members148 and 220, as will be hereinafter described.

Disposed on upper opposite ends of the scaffold of the invention, asshown in FIG. 10, are control assemblies 228 and 230 similar to theassemblies 100 and 102, shown in FIG. 4 of the drawings.

It will be seen from FIG. 11, that diagonal braces 232 and 234 areconnected to the cross member 198 near the clevis 196 and that upperopposite ends of the braces 232 and 234 are extended angularly outwardand are pivotally connected to the upper ends of the braces 204 and 208.In this manner, the sides and the ends of the scaffold are braced so asto transfer through the diagonal braces 232 and 234 forces imposed bythe cylinder plunger 194 and to assist the cross member 198 insupporting this load. In a similar manner, braces 236 and 238 areconnected to the cross member 182 and downwardly and outwardly extendingportions 240 and 242 of these braces 236 and 238 are pivotally connectedto the lower ends of the braces 222 and 224. Accordingly, load from theplunger 198 is carried partly in tension by the braces 240 and 242transferred to the diagonal braces 222 and 224 and also the braces 216and 218.

As shown in FIG. 13, it will be seen that the braces 204 and 208 attheir connections 206 are secured to an angle member 248 which isconnected to a bar 250 secured to the internal column member 212. Thebar 250 operating vertically in a vertical slot 251 disposed in thehollow cylindrical column member 252 which is similar to the hollowcylindrical column member 149. A similar arrangement exists with respectto the braces 222 and 224 and the diagonals 236 and 238 and with respectto the hollow cylindrical column members 148 and 220, such that theupwardly extending internal column members 150 may retract downwardlyvertically into the hollow cylindrical column members 148 and permit thebraces 222 and 224 connected to a bar 225 to traverse a slot 221 in thecylindrical member 220 to move downwardly together with the internalcolumn members 150 and the diagonals 236 and 238. Thus, all of thecorner assemblies are constructed.

It will be obvious to those skilled in the art that variousmodifications of the present invention may be resorted to in a mannerlimited only by a just interpretation of the following claims.

I claim:

1. In a scaffold the combination of: a generally rectangular scaffoldstructure having four corners and first and second ends; four verticallyextendable telescopic column assemblies; each of said column assembliesdisposed at one of said four corners; a first pair of said columnassembiles disposed at said first end of said scaffold structure; asecond pair of said column assemblies disposed at said second end ofsaid scaffold structure; first means coupled to said first pair oftelescopic column members and disposed to extend said first pairvertically; second means coupled to said second pair of verticallyextendable column members and disposed to extend said second pairvertically and independently relative to said first pair, whereby eachof said pair may be independently extended to an elevation differentfrom that of the other pair; and deck means abridging and supported bysaid first and second pairs of column members, whereby said deck meansmay be supported on an incline relative to the horizontal when one ofsaid pairs of column assemblies is telescopically extended and disposedat an elevation different from that of the other pair of column members;first and second relatively movable sections of each of said assemblies;cross bars interconnecting said first and second sections, respectively,of each of said pairs of assemblies; said first means extendable andinterconnecting said cross bars of said first and second sections,respectively, at locations substantially midway between the columnassemblies of each pair of column assemblies.

2. In a scaffold the combination of: a generally rectangular scaffoldstructure having four corners and first and second ends; four verticallyextendable telescopic column assemblies; each of said column assembliesdisposed at oneof said four corners; a first pair of said columnassemblies disposed at said first end of said scaffold structure; asecond pair of said column assemblies disposed at said second end ofsaid scaffold structure; first means coupled to said first pair oftelescopic column members and disposed to extend said first pairvertically; second means coupled to said second pair of verticallyextendable column members and disposed to extend said second pairvertically and independently relative to said first pair, whereby eachof said pair may be independently extended to an elevation differentfrom that of the other pair; and deck means abridging and supported bysaid first and second pairs of column members, whereby said deck meansmay be supported on an incline relative to the horizontal when one ofsaid pairs of column assemblies is telescopically extended and disposedat an elevation different from that of the other pair of column members;first and second relatively movable sections of each of said assemblies;cross bars interconnecting said first and second sections, respectively,of each of said pairs of assemblies; said first means extendable andinterconmeeting said cross bars of said first and second sections,respectively, at locations substantially midway between the columnassemblies of each pair of column assemblies; said first means being ahydraulic cylinder and plunger actuator.

3. In a scaffold the combination of: a generally rectangular scaffoldstructure having four corners and first and second ends; four verticallyextendable telescopic column assemblies; each of said column assembliesdisposed at one of said four corners; a first pair of said columnassemblies disposed at said first end of said scaffold structure; asecond pair of said column assemblies disposed at said second end ofsaid scaffold structure; first means coupled to said first pair oftelescopic column members and disposed to extend said first pairvertically; second means coupled to said second pair of verticallyextendable column members and disposed to extend said second pairvertically and independently relative to said first pair, whereby eachof said pair may be independent? ly,,ex tended .to an elevationdifferent from that off the other pair; and .deck means abridgingandsupported by said first and second pairs of column members whereby saiddeck means may be supported on an incline relative to the horizontalwhen oneof said pairs of column assemblies is telescopically extendedand disposed at an elevation different from that of'the other pair ofcolumn members;..first, and .secondrelati'vely movable sections ofeach-of saidassemblies; cross bars interconnecting said first and secondsections, respectively, of each of" said pairs of assemblies; said firstmeans extendable and interconnecting .said. cross bars of said first andsecond sections, respectively, at locations substantially midway betweenthe column assembliesof each pair of columnvas: semblies; said firstsections of each column assembly being hollow and containing said secondsection, each of said first sections having a vertically disposedslotted side wall through which cross bars, connecting said respectivesecond sections, extend.

4. In a scaffold the combination of: a generally rectangular scaffoldstructure having four corners and first and second ends; four verticallyextendable telescopic column assemblies; each of said column assembliesdis posed at one of said four corners; a first pair of said columnassemblies disposed at said first end of said scaffold structure; asecond pair of said column assemblies disposed at said second end ofsaid scaffold structure; first means coupled to said first pair oftelescopic column members and disposed to extend said first pairvertically; second means coupled to said second pair of verticallyextendably column members and disposed to extend said second pairvertically and independently relative to said first pair, whereby eachof said pair may be independently extended to an elevation differentfrom that of the other pair; and deck means abridging and supported bysaid first and second pairs of column members, whereby said deck meansmay be supported on an incline relative to the horizontal when one ofsaid pairs of column assemblies is telescopically extended and disposedat an elevation different from that of the other pair of column members;each of said column assemblies comprising three concentric relativelytelescopic sections; brace means interconnecting said telescopicsections; vertically slotted portions of some of said sections disposedand receiving said brace means interconnecting some of the othertelescopic sections of each column assembly.

5. In a scaffold the combination of: a generally rectangular scaffoldstructure having four comers and first and second ends; four verticallyextendable telescopic column assemblies; each of said column assembliesdisposed at one of said four corners; a first pair of said columnassemblies disposed at said first end of said scaffold structure; asecond pair of said column assemblies disposed at said second end ofsaid scaffold structure; first means coupled to said first pair oftelescopic column members and disposed to extend said first pairvertically; second means coupled to said second pair of verticallyextendable column members and disposed to extend said second pair ofvertically and independently relative to said first pair, whereby eachof said pair may be independently extended to an elevation differentfrom that of the other pair; and deck means abridging and supported bysaid first and second pairs of column members, whereby said deck meansmay be supported on an incline relative to the horizontal when one ofsaid pairs of column assemblies is telescopically extended and disposedat an elevation different from that of the other pair of column members;first and second relatively movable sections of each of said assemblies;cross bars interconnecting said first and second sections, respectively,of each of said pairs of assemblies; said first means extendable andinterconnecting said cross bars of said first and second sections,respectively, at locations substantially midway between the columnassemblies of each pair of column assemblies; said first sections ofeach column assembly being hollow and containing said second section,each of said first sections having a vertically disposed slotted sidewall through which cross bars, connecting said respective secondsections,extend; braces interconnecting said first and second pairs ofcolumn assemblies at said first and second ends, respectively, of saidscaffold structure, t

6. In a scaffold the combination of: a generally, rec tangular scaffoldstructure having four corners and first and secondends; tour verticallyextendable telescopic column assemblies; each of said column assembliesdisposed at one of said four corners; a first pair of said columnassemblies disposed at said first end of said scaffold structure; asecond pair of said column assemblies disposed at saidsecond end of saidscaffold structure; first hydraulic cylinder 'means coupled to saidfirst pair of telescopic column members and disposed to extend saidfirst pair vertically; second hydraulic cylinder means coupled to saidsecond pair of vertically extendable column members and disposed toextend said second pair vertically and independently relative to saidfirst pair, whereby each of said pairs may be independently extended toan elevation different from that of the other pair; and deck meansabridging and supported by said first and second pairs of columnmembers, whereby said deck means may be supported on an incline relativeto the horizontal when one of said pairs of column assemblies istelescopically extended and disposed at an elevation different from thatof the other pair of column members; motor and pump means carried bysaid scaffold structure and disposed to deliver hydraulic pressure fluidto said hydraulic cylinders.

7. In a scaffold the combination of: a generally rectangular scaffoldstructure having four corners and first and second ends; four verticallyextendable telescopic column assemblies; each of said column assembliesdisposed at one of said four corners; a first pair of said columnassemblies disposed at said first end of said scaffold structure; asecond pair of said column assemblies disposed at said second end ofsaid scaffold structure; and cross angular brace means interconnectingsaid column assemblies at said sides and ends of said scaffold; firstmeans coupled to said first pair of telescopic column members anddispose-d to extend said first pair vertically; second means coupled tosaid second pair of vertically extendable column members and disposed toextend said second pair vertically and independently relative to saidfirst pair whereby each of said pair may be independently extended to anelevation different from that of the other pair; and deck meansabridging and supported by said first and second pairs of columnmembers, whereby said deck means may be supported on an incline relativeto the horizontal when one of said pairs of column assemblies istelescopically extended and disposed at an elevation different from thatof the other pair of column members; each column assembly comprisesfirst and second external hollow cylindrical column members disposedvertically and parallel to each other and fixed in contiguousrelationship to each other, said hollow cylindrical column membershaving upper and lower ends; first and second internal column memberstelescopically slidably mounted in said first and second externalcylindrical members, respectively, said first internal column memberstelescopically extendable upwardly from an upper end of said firstexternal cylindrical members and said second external column memberstelescopically extendable downwardly from a lower end of said secondexternal column members.

8. The invention, as defined in claim 7, wherein: said first and secondmeans each comprising first and second power operated actuators fixedrespectively to said first and second external hollow cylindrical columnmembers; power operated extendable and retractable members for saidactuators, said first actuators having their said extendable membersextendable upwardly and retractable downwardly, said first actuatorhaving its extendable member connected to said first internal columnmembers of a respective pair of said column assemblies; said second Iactuators having their said extendable members extendable downwardly andretractable upwardly, said second actuators having their extendablemembers connected to said second internal column members of a respectivepair of said column assemblies.

9. The invention, as defined in claim 8, wherein: each of said firsthollow cylindrical column members is disposed inwardly *from arespective end of said scaffold with respect to respective ones of saidhollow cylindrical column members.

10. The invention, as defined in claim 8, wherein: uppermost telescopicmembers are upwardly extendably mounted on said first internal columnmembers and said first r e A 7 each of said pairs of internal columnmembers and disposed to vertically extend upward and retract downwardlyto move said uppermost telescopic members relative to said firstinternal column members.

References Cited UNITED STATES PATENTS 2,657,009 10/1953 Neis 254-932,692,169 10/1954 Phillips 182141 2,993,561 7/1961 Watson 182-1953,017,968 1/1962 McMahon 182141 3,028,928 4/1962 Iuculano 182-178 andsecond means also comprising actuating means on 5 REINALDO P. MACHADO,Primary Examiner.

